Learn more

Study finds serious mental illness not a barrier to weight loss

March 22, 2013

A new study found that a behavioural weight loss program helped people with serious mental illnesses lose weight.

Being obese or overweight is very common among people with serious mental illnesses such as schizophrenia, bipolar disorder and major depression. This puts them at risk for obesity-related health conditions such as diabetes and heart disease. According to background information in the study, people with major mental illnesses have more than double the mortality rate compared to the rest of the population, and cardiovascular disease is a common cause of death.

The study authors also note that many weight-loss studies exclude people with major mental illnesses. There may be a belief that people with these conditions may be less able to make lifestyle changes because they may have symptoms that make behaviour changes more challenging.

However, a specialized program was successful in helping people with serious mental illnesses lose weight. The program involved group and individual weight-management sessions, as well as group exercise sessions, and lasted 18 months.

For the study, researchers compared weight-loss success in 144 people in the program to weight loss in 147 people who were not in the program. Those not in the program received standard care: they were given nutrition and exercise information at the start of the study. All of the participants had a serious mental illness: 58 per cent had schizophrenia or a schizoaffective disorder, 22 per cent had bipolar disorder, 12 per cent had major depression and eight per cent had other conditions.

All of the participants were overweight or obese at the start of the study. The average body mass index (BMI) at the start of the study was 36.3, and the average weight was 103 kilograms (226 pounds).

Over the 18-month study period, the people in the program lost significantly more weight than those who were not. The program participants lost an average of 3.2 kilograms (seven pounds) more than the other participants. They were also more likely to achieve significant weight loss: the number of program participants who lost at least five per cent of their body weight was 38 per cent, compared to 23 per cent of those not in the program. The number of program participants who lost 10 per cent of their body weight or more was almost 19 per cent, compared to seven per cent of those not in the program.

These results show that people with serious mental illnesses can make healthy lifestyle changes despite facing challenges. Because of the high rates of obesity and being overweight among people with serious mental illnesses, the study authors recommend weight-loss programs tailored to this audience.

The study was published online in the New England Journal of Medicine on March 21, 2013.